Vessel propulsion system and vessel including the same

ABSTRACT

A propulsion system for a vessel includes an engine propulsion unit that provides a propulsive force to a hull by using an engine as a power source, an electric propulsion unit that provides a propulsive force to the hull by using an electric motor as a power source, a storing mechanism that is displaced from an actuating position to actuate the electric propulsion unit to a storing position to store the electric propulsion unit and performs a storing operation to store the electric propulsion unit, and an interlock controller that interlocks a storing operation of the storing mechanism with generation of a propulsive force by the engine propulsion unit.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority to Japanese PatentApplication No. 2016-221862 filed on Nov. 14, 2016. The entire contentsof this application are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a vessel propulsion system including anelectric propulsion unit and a vessel including such a vessel propulsionsystem.

2. Description of the Related Art

United States Patent Application Publication No. 2016/0185431 A1discloses a vessel including an electric propulsion unit. An electricpropulsion unit is a propulsion unit using an electric motor as a powersource. As compared with an engine propulsion unit conventionally used,that is, a propulsion unit using an internal combustion as a powersource, the electric propulsion unit produces little noise, and hasexcellent steering stability at the time of low-speed traveling.

SUMMARY OF THE INVENTION

The inventors of preferred embodiments of the present inventiondescribed and claimed in the present application conducted an extensivestudy and research regarding a vessel propulsion system, such as the onedescribed above, and in doing so, discovered and first recognized newunique challenges and previously unrecognized possibilities forimprovements as described in greater detail below.

A propulsive force generated by an electric propulsion unit does notalways meet users' demands. For example, an output of the electricpropulsion unit is not sufficient for high-speed traveling, and in thiscase, an engine propulsion unit is preferred.

Therefore, the inventors of the preferred embodiments of the presentinvention have studied an arrangement of a vessel including an enginepropulsion unit in addition to an electric propulsion unit.

In a case in which both of an electric propulsion unit and an enginepropulsion unit are equipped on a vessel, when the vessel travels byobtaining a propulsive force from the engine propulsion unit, and whenthe electric propulsion unit is in the water, the electric propulsionunit generates a resistance against traveling. Accordingly, fuelefficiency deteriorates and a traveling speed becomes low. Therefore,the inventors of preferred embodiments of the present inventionconsidered providing a storing mechanism that stores the electricpropulsion unit when it is not used. However, when using a propulsiveforce generated by the engine propulsion unit, if an operation to storethe electric propulsion unit is left to a user, vessel operation becomescomplicated. Therefore, the user may not store the electric propulsionunit. Therefore, even when the storing mechanism is provided,improvement in fuel efficiency and an excellent traveling speed whenusing an engine propulsion unit cannot be necessarily realized.

Preferred embodiments of the present invention provide vessel propulsionsystems and vessels that solve the above problem.

In order to overcome the previously unrecognized and unsolved challengesdescribed above, a preferred embodiment of the present inventionprovides a vessel propulsion system including an engine propulsion unitthat provides a propulsive force to a hull by using an engine as a powersource, an electric propulsion unit that provides a propulsive force tothe hull by using an electric motor as a power source, a storingmechanism that performs a storing operation to move the electricpropulsion unit from an actuating position to a storing position tostore the electric propulsion unit, and an interlock controllerconfigured or programmed to interlock the storing operation of thestoring mechanism with generation of a propulsive force by the enginepropulsion unit.

With this arrangement, even when a user does not perform a specialoperation to store the electric propulsion unit, generation of apropulsive force by the engine propulsion unit and storing of theelectric propulsion unit are interlocked with each other. Accordingly,when the vessel is made to travel by a propulsive force of the enginepropulsion unit, traveling resistance caused by an electric propulsionunit is significantly reduced or prevented. Accordingly, fuel efficiencyis improved, and excellent traveling performance is obtained.

In a preferred embodiment of the present invention, in response toactuation of the storing mechanism to store the electric propulsionunit, the interlock controller allows generation of a propulsive forceby the engine propulsion unit. Accordingly, when the vessel is made totravel by a propulsive force of the engine propulsion unit, travelingresistance caused by the electric propulsion unit is significantlyreduced or prevented.

In a preferred embodiment of the present invention, when an acceleratoroperation amount, which is an operation amount of an accelerator that isoperated by a vessel operator to adjust a propulsive force of thevessel, reaches a predetermined threshold or more, the interlockcontroller causes the storing mechanism to perform a storing operation.Accordingly, when an accelerator operation amount reaches thepredetermined threshold or more and a large propulsive force is needed,the electric propulsion unit is stored, and generation of a propulsiveforce by the engine propulsion unit is allowed. Therefore, a largepropulsive force is generated by the engine propulsion unit to make thevessel travel, and at this time, traveling resistance caused by theelectric propulsion unit is significantly reduced or prevented.

In a preferred embodiment of the present invention, in response togeneration of a propulsive force by the engine propulsion unit, theinterlock controller causes the storing mechanism to perform the storingoperation. Accordingly, when the vessel is made to travel by apropulsive force from the engine propulsion unit, traveling resistancecaused by the electric propulsion unit is significantly reduced orprevented.

In a preferred embodiment of the present invention, when an acceleratoroperation amount, which is an operation amount of an accelerator that isoperated by a vessel operator to adjust a propulsive force of thevessel, reaches a predetermined threshold or more, the interlockcontroller allows generation of a propulsive force by the enginepropulsion unit.

Accordingly, when the accelerator operation amount reaches or exceedsthe predetermined threshold and a large propulsive force is needed,generation of a propulsive force by the engine propulsion unit isallowed. Then, when the engine propulsion unit generates a propulsiveforce, in response to this, the electric propulsion unit is stored.Therefore, a large propulsive force is generated by the enginepropulsion unit to make the vessel travel, and at this time, travelingresistance caused by the electric propulsion unit is significantlyreduced or prevented.

In a preferred embodiment of the present invention, the interlockcontroller causes the storing mechanism to perform the storing operationwhen an accelerator operation amount, which is an operation amount of anaccelerator that is operated by a vessel operator to adjust a propulsiveforce of the vessel, reaches a predetermined storing threshold or more,and allows generation of a propulsive force by the engine propulsionunit when the accelerator operation amount reaches an engine propulsionthreshold or more. Accordingly, when the accelerator operation amount isa large value and a large propulsive force is needed, the electricpropulsion unit is stored, and generation of a propulsive force by theengine propulsion unit is allowed. Thus, based on the acceleratoroperation amount, storing of the electric propulsion unit and generationof a propulsive force by the engine propulsion unit are interlocked witheach other. Therefore, when a large propulsive force is generated fromthe engine propulsion unit to make the vessel travel, travelingresistance caused by the electric propulsion unit is significantlyreduced or prevented.

In a preferred embodiment of the present invention, the vesselpropulsion system further includes a propulsion mode switch thatswitches between an engine propulsion allowing state in which generationof a propulsive force by the engine propulsion unit is allowed and anelectric propulsion allowing state in which generation of a propulsiveforce by the electric propulsion unit is allowed. The propulsion modeswitch may include a mode switch to be operated by a user.

In a preferred embodiment of the present invention, switching betweenthe engine propulsion allowing state and the electric propulsionallowing state by the propulsion mode switch includes a transition statein which generation of a propulsive force by the engine propulsion unitis allowed and generation of a propulsive force by the electricpropulsion unit is allowed. That is, in the transition state, both ofthe electric propulsion unit and the engine propulsion unit are allowedto generate propulsive forces.

In a preferred embodiment of the present invention, the enginepropulsion unit includes the engine, a propulsive force generator, and aclutch disposed in a driving force transmission path from the engine tothe propulsive force generator, and the interlock controller allowsoperation of the engine if the clutch is in a disengaged state whengeneration of a driving force by the engine propulsion unit is notallowed.

With this arrangement, in a clutch disengaged state, operation of theengine is allowed. Therefore, for example, when the engine propulsionunit is provided with a power generator, a battery is able to be chargedby electric power generated by the power generator, and electricfacilities on the vessel are able to be used.

A preferred embodiment of the present invention provides a vesselincluding a hull, and a vessel propulsion system including featuresdescribed above provided on the hull. In this vessel, even when a userdoes not perform a special operation to store the electric propulsionunit, generation of a propulsive force by the engine propulsion unit andstoring of the electric propulsion unit are interlocked with each other.Accordingly, when the vessel is made to travel by a propulsive force ofthe engine propulsion unit, traveling resistance caused by the electricpropulsion unit is significantly reduced or prevented. Therefore, fuelefficiency is improved, and excellent traveling performance is obtained.

The above and other elements, features, steps, characteristics andadvantages of the present invention will become more apparent from thefollowing detailed description of the preferred embodiments withreference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic longitudinal sectional view to describe an exampleof a vessel according to a preferred embodiment of the presentinvention.

FIG. 2 is a schematic plan view of the vessel.

FIG. 3 is a schematic side view to describe an example of an enginepropulsion unit.

FIG. 4 is a perspective view to describe an example of an electricpropulsion unit.

FIG. 5 is a longitudinal sectional view of the electric propulsion unit.

FIG. 6 is a block diagram to describe an electrical configuration of thevessel.

FIG. 7 is a flowchart showing an example of a process in associationwith interlocking operation of a storing mechanism and propulsive forcegeneration by the engine propulsion unit.

FIG. 8 is a diagram to describe a second preferred embodiment of thepresent invention, and is a flowchart showing an example of a process inassociation with an interlocking operation of a storing mechanism andpropulsive force generation by an engine propulsion unit.

FIGS. 9A and 9B are diagrams to describe a third preferred embodiment ofthe present invention, and are flowcharts showing examples of processesin association with interlocking operation of a storing mechanism andpropulsive force generation by an engine propulsion unit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a schematic longitudinal sectional view to describe an exampleof a vessel 1 according to a preferred embodiment of the presentinvention, and FIG. 2 is a plan view of the same. The vessel 1 includesa hull 2, and an engine propulsion unit 3 and an electric propulsionunit 4 provided on the hull 2. This vessel 1 preferably is, for example,a so-called pontoon boat, and the hull 2 includes a deck 2 a, a pair offloats 2 b integral with a lower surface of the deck 2 a, and aperipheral wall 2 c that rises from an upper surface of the deck 2 a anddefines a cabin 2 d. A cockpit 5 is disposed inside the cabin 2 d. Asteering wheel 5 a, a shift lever 5 b, and a joystick 5 c, etc., aredisposed in the cockpit 5. In the cockpit 5, a vessel operator seat 35is disposed. A seat 36 for occupants is disposed inside the cabin 2 d.The pontoon boat is just one example of the vessel, and preferredembodiments of the present invention is also applicable to vessels ofother types and shapes.

The pair of floats 2 b extend in the front-rear direction along lowersurface right and left sides of the deck 2 a. Between the pair of floats2 b, a propulsion unit attaching bracket 6 is fixed to a lower surfaceof the deck 2 a. An engine propulsion unit 3 and an electric propulsionunit 4 are attached to the propulsion unit attaching bracket 6. Thepropulsion unit attaching bracket 6 extends in the front-rear directionof the hull 2, and a rear end of the bracket reaches a rear end portionof the deck 2 a. An attaching plate 6 a is provided at a rear end of thepropulsion unit attaching bracket 6. The engine propulsion unit 3 isattached to the attaching plate 6 a. The electric propulsion unit 4 isdisposed ahead of the attaching plate 6 a, and is attached to thepropulsion unit attaching bracket 6 via a storing mechanism 8. Thestoring mechanism 8 rotationally moves the electric propulsion unit 4around a storing rotational movement axis 9 extending in the right-leftdirection of the hull 2. Accordingly, the storing mechanism 8 is able todisplace the electric propulsion unit 4 between a storing position(shown by a phantom line in FIG. 1) stored in a storing space 7compartmented on an inner side of the propulsion unit attaching bracket6, and an actuating position (shown by the solid line in FIG. 1)extending to the lower side of the deck 2 a and projecting from thestoring space 7.

FIG. 3 is a schematic side view used to describe an example of theengine propulsion unit 3. In the present preferred embodiment, theengine propulsion unit 3 is an internal combustion engine drivenoutboard motor. The engine propulsion unit 3 includes a cover 11, anengine 12, a propeller 13, a power transmission 14, and a bracket 15.The cover 11 houses the engine 12 and the power transmission 14. Theengine 12 is disposed in an upper space inside the cover 11. The engine12 is a power source that generates a propulsive force. The propeller 13is driven to rotate by a driving force generated by the engine 12. Thepropeller 13 is disposed outside the cover 11 at a lower portion of theengine propulsion unit 3. The power transmission 14 transmits a drivingforce of the engine 12 to the propeller 13. The power transmission 14includes a drive shaft 16, a propeller shaft 17, and a shift mechanism18.

The drive shaft 16 is disposed along the up-down direction. The driveshaft 16 is joined to a crankshaft 19 of the engine 12, and transmitspower generated by the engine 12. The propeller shaft 17 is disposedalong the front-rear direction. The propeller shaft 17 is joined to alower portion of the drive shaft 16 via the shift mechanism 18. Thepropeller shaft 17 transmits a driving force of the drive shaft 16 tothe propeller 13.

The shift mechanism 18 switches a rotation direction of power to betransmitted from the drive shaft 16 to the propeller shaft 17. The shiftmechanism 18 includes a pinion gear 21, a forward gear 22, a backwardgear 23, and a dog clutch 24. The pinion gear 21 is fixed to a lower endof the drive shaft 16. The forward gear 22 and the backward gear 23 aredisposed on the propeller shaft 17, and are rotatable relative to thepropeller shaft 17. The pinion gear 21 engages with the forward gear 22and the backward gear 23. The dog clutch 24 is spline-coupled to thepropeller shaft 17, and disposed between the forward gear 22 and thebackward gear 23. The dog clutch 24 is movable along the propeller shaft17, and rotates together with the propeller shaft 17. The dog clutch 24is movable to a forward position, a neutral position, and a backwardposition on the propeller shaft 17. The forward position is a positionat which the dog clutch 24 engages with the forward gear 22, and doesnot engage with the backward gear 23. The backward position is aposition at which the dog clutch 24 engages with the backward gear 23,and does not engage with the forward gear 22. The neutral position is aposition at which the dog clutch 24 does not engage with any of theforward gear 22 and the backward gear 23, and is located between theforward position and the backward position. When the dog clutch 24 is atthe forward position, rotation of the drive shaft 16 is transmitted tothe propeller shaft 17 via the forward gear 22. Accordingly, thepropeller 13 rotates in a forward-traveling rotation direction togenerate a propulsive force to propel the hull 2 forward. When the dogclutch 24 is at the backward position, rotation of the drive shaft 16 istransmitted to the propeller shaft 17 via the backward gear 23.Accordingly, the propeller 13 rotates in a backward-traveling rotationdirection to generate a propulsive force to propel the hull 2 backward.When the dog clutch 24 is at the neutral position, neither of rotationsof the forward gear 22 and the backward gear 23 is transmitted to thepropeller shaft 17. Therefore, no driving force is transmitted to thepropeller 13.

The shift mechanism 18 further includes a shift rod 25 to move the dogclutch 24 along the propeller shaft 17. The shift rod 25 is driven by ashift actuator 26. Therefore, by controlling operation of the shiftactuator 26, the dog clutch 24 is able to be controlled to any of theforward position, the neutral position, and the backward position.Hereinafter, a position of the dog clutch 24 may be referred to as“shift position.” The dog clutch 24 is an example of a clutch thatcuts-off/shuts-off a driving force transmission path from the engine 12to the propeller 13.

The bracket 15 attaches the engine propulsion unit 3 to the hull 2, andis attached to the attaching plate 6 a of the propulsion unit attachingbracket 6. The engine propulsion unit 3 is attached to the bracket 15and is rotatable around a tilt shaft 31 and a turning shaft 32. The tiltshaft 31 extends in a width direction (horizontal direction) of the hull2. The turning shaft 32 is perpendicular or substantially perpendicularto the tilt shaft 31, and extends substantially along the up-downdirection in a state in which the engine propulsion unit 3 is used. Atilt trim actuator 27 rotationally moves the engine propulsion unit 3around the tilt shaft 31. By rotationally moving the engine propulsionunit 3 around the tilt shaft 31, a trim angle of the engine propulsionunit 3 is changed. The trim angle corresponds to an attaching angle ofthe engine propulsion unit 3 to the hull 2.

A turning mechanism 30 changes a direction of a propulsive force to begenerated by the engine propulsion unit 3 to the rightward or leftwarddirection of the hull 2. The turning mechanism 30 rotationally moves theengine propulsion unit 3 around the turning shaft 32. The turningmechanism 30 includes a turning actuator 28 as a power source. Byrotationally moving the engine propulsion unit 3 around the turningshaft 32 by the turning mechanism 30, a turning angle is changed. Theturning angle is an angle (angle of direction) that a propulsive forceof the engine propulsion unit 3 makes with respect to the front-reardirection of the hull 2.

FIG. 4 is a perspective view to describe an example of the electricpropulsion unit, and FIG. 5 is a longitudinal sectional view of thesame. The electric propulsion unit 4 includes a cylindrical duct 41, apropeller 42, a steering shaft 43, a casing 44, a motor controller 45,and a turning mechanism 46. The duct 41 includes a stator 47. Thepropeller 42 includes a rim 51 and blades 52. The rim 51 includes arotor 53. The stator 47 and the rotor 53 face each other, and theseelements define an electric motor 50 (switched reluctance motor). Thatis, by applying a current to the stator 47, the rotor 53 rotates arounda rotation axis A. As the electric motor 50, other than a switchedreluctance motor (SR motor), a permanent magnet motor or a steppingmotor may be used.

The duct 41 is a rotary body in which the rotation axis A is an axis ofrotation, and its cross section in a plane including the rotation axis Ais wing-shaped. That is, the cross section has a shape that is round ata front edge and pointed at a rear edge. An inner diameter (radius of aninner circumferential surface) of the duct 41 decreases toward the rearside in a region in front of the blades 52, and is almost uniform in aregion from the blades 52 to the rear edge. An outer diameter (radius ofan outer circumferential surface) of the duct 41 is almost uniform inthe region in front of the blades 52, and decreases toward the rear sidein the region from the blades 52 to the rear edge.

On the inner circumferential surface of the duct 41, a circumferentialrecess recessed radially outward is provided. The rim 51 is housed inthis recess. More specifically, the rim 51 is supported rotatably by theduct 41 via a fluid bearing 49 provided along the recess of the duct 41.

On the outer circumference of the recess of the duct 41, the stator 47is disposed. The stator 47 includes coils. The stator 47 generates amagnetic field when electric power is supplied to the coils. A pluralityof coils are disposed circumferentially along the recess of the duct 41.Electric power is respectively supplied to the plurality of coils insynchronization with rotation. Accordingly, a magnetic force of thestator 47 is applied to the rotor 53 of the propeller 42, andaccordingly, the propeller 42 is rotated.

The blades 52 of the propeller 42 are located on the inner side of thering-shaped rim 51, and radially outer edges of the blades are fixed toan inner circumferential surface of the rim 51. That is, the blades 52project inward in the radial direction of the rim 51 from the innercircumferential surface of the rim 51. For example, four blades 52 areprovided at even intervals (of about 90 degrees) along thecircumferential direction. The blades 52 are preferably wing-shaped.

The rotor 53 is provided on the outer side of the rim 51. The rotor 53is disposed at a position facing the stator 47 of the duct 41. Morespecifically, the rotor 53 and the stator 47 face each other at apredetermined distance in the radial direction. That is, the electricmotor 50 including the stator 47 and the rotor 53 preferably is a radialgap type motor, for example. In the rotor 53, a portion with highmagnetic permeability and a portion with low magnetic permeability arealternately disposed circumferentially. That is, in the rotor 53, areluctance torque is generated by a magnetic force generated from thestator 47. Accordingly, the rotor 53 (rim 51) is rotated.

The steering shaft 43 turnably supports the duct 41. More specifically,the steering shaft 43 is supported rotatably by the turning mechanism 46via a tapered roller bearing 55. The steering shaft 43 supports, via thetapered roller bearing 55, the casing 44 which is integral with the duct41. The motor controller 45 is housed in the casing 44. The steeringshaft 43 preferably has a hollow shape. Inside the hollow shape of thesteering shaft 43, wiring that supplies electric power to the stator 47,wiring to connect the motor controller 45 and a battery (not shown)equipped in the hull 2, wiring to connect an inboard LAN (Local AreaNetwork) 91 (refer to FIG. 6) and the motor controller 45, and wiring toconnect the motor controller 45 and the turning mechanism 46, etc., arehoused.

In the present preferred embodiment, the casing 44 is fixed to the duct41 and turns together with the duct 41. More specifically, the casing 44is integral with the duct 41. The casing 44 preferably has a streamlinedshape along the rotation axis A of the propeller 42. More specifically,the casing 44 preferably has a streamlined shape so that its resistanceto water relatively flowing in the direction X along the rotation axis Ais small. In greater detail, the duct 41 and the casing 44 arepreferably wing-shaped in cross section. Therefore, the duct 41 and thecasing 44 generate a propulsive force by a wing effect when a water flowin a direction X2 from the front edge to the rear edge of the duct 41 isgenerated. On the other hand, the duct 41 and the casing 44, when awater flow in a reverse direction X1 is generated, hardly generate apropulsive force attributable to this water flow. This causes adifference between a propulsive force in the direction X1(forward-traveling direction) generated by rotating the portion 42forward and a propulsive force in the direction X2 (backward-travelingdirection) generated by reversely rotating the propeller 42 even thoughthe rotation speed is the same. That is, the propulsive force in thedirection X1 (forward-traveling direction) is larger.

The turning mechanism 46 is disposed above the duct 41, and turns theduct 41. The turning mechanism 46 includes an electric motor 60, areducer 61, and a turning angle sensor 62. The electric motor 60 of theturning mechanism 46 is driven based on a command from a controller 90(refer to FIG. 6). The electric motor 60 is driven to rotate whensupplied with electric power from a battery (not shown) equipped in thehull 2 via a driver. The electric motor 60 rotates the steering shaft 43around a turning axis B via the reducer 61. The turning angle sensor 62detects a rotational movement angle of the steering shaft 43 as aturning angle. Based on a detected turning angle, the electric motor 60is feedback-controlled.

FIG. 5 also shows an examples of the structure that attaches theelectric propulsion unit 4 to the hull 2. An upper surface of theturning mechanism 46 is fixed to the bracket 57. Accordingly, theelectric propulsion unit 4 is supported by the bracket 57.

The bracket 57 is attached to the propulsion unit attaching bracket 6via the storing mechanism 8 that moves rotationally around a storingrotational movement axis 9 extending in the right-left direction of thehull 2. More specifically, the storing mechanism 8 includes a drivebracket 79 (a movable portion), and an electric motor 80 thatrotationally moves the drive bracket 79 around the storing rotationalmovement axis 9. The bracket 57 includes a hull attachment 71 and apropulsion unit attachment 72. The hull attachment 71 is coupled to thedrive bracket 79 of the storing mechanism 8, and is arranged so that adriving force from the storing mechanism 8 is transmitted to the hullattachment 71. The propulsion unit attachment 72 defines a predeterminedangle with respect to the hull attachment 71 and is integral with thehull attachment 71. The propulsion unit attachment 72 preferably has atabular or substantially tubular shape. The upper surface of the turningmechanism 46 is fixed to the propulsion unit attachment 72.

The storing mechanism 8 rotationally moves (displaces) the drive bracket57 around the storing rotational movement axis 9 between an actuatingposition shown by the solid line and a storing position shown by thephantom line. Accordingly, the electric propulsion unit 4 rotationallymoves around the storing rotational movement axis 9, and is displacedbetween the actuating position shown by the solid line and the storingposition shown by the phantom line. The storing position is a positionat which the electric propulsion unit 4 is stored in a storing space 7inside the propulsion unit attaching bracket 6.

FIG. 6 is a block diagram to describe an electrical configuration of thevessel. The vessel 1 includes the controller 90. The controller 90, theengine propulsion unit 3, the electric propulsion unit 4, and thestoring mechanism 8 define a vessel propulsion system 100 according to apreferred embodiment of the present invention. Input signals from thesteering wheel 5 a, the shift lever 5 b, the joystick 5 c, and the modeswitch 5 d are input into the controller 90. More specifically, inrelation to the steering wheel 5 a, an operation angle sensor 75 a thatdetects an operation angle of the steering wheel 5 a is provided. Inaddition, in relation to the shift lever 5 b, an accelerator openingdegree sensor 75 b including a position sensor that detects an operationposition (operation amount) of the shift lever 5 b is provided. Further,in relation to the joystick 5 c, a joystick position sensor 75 cincluding a position sensor that detects an operation position of thejoystick 5 c is provided. Detection signals of these sensors 75 a, 75 b,and 75 c and an output signal of the mode switch 5 d are input into thecontroller 90. An output signal of a vessel speed sensor 76 that detectsa vessel speed of the vessel 1 is input to the controller 90. Thecontroller 90 is an example of an interlock controller in a preferredembodiment of the present invention.

The controller 90 is connected to the inboard LAN 91. The turningmechanism 46 of the electric propulsion unit 4 includes, as describedabove, an electric motor 60 (hereinafter, referred to as a “turningmotor 60”) as a drive source. The storing mechanism 8 includes anelectric motor 80 (hereinafter, referred to as “storing motor 80”) as adrive source. An electric motor 50 (hereinafter, referred to as“propulsion motor 50”) that rotationally drives the propeller 42, theturning motor 60, and the storing motor 80 are actuated by a drivecurrent supplied from the motor controller 45. The motor controller 45is connected to the inboard LAN 91. The controller 90 communicates withthe motor controller 45 via the inboard LAN 91, and provides a drivecommand value to the motor controller 45. To the inboard LAN 91, acontroller of the engine propulsion unit 3, that is, an engine ECU(Electronic Control Unit) 20 is further connected.

The motor controller 45 includes a turning motor controller 85 to drivethe turning motor 60, a propulsion motor controller 86 to drive thepropulsion motor 50, and a storing motor controller 87 to drive thestoring motor 80.

The turning motor controller 85 includes an output computer 85 a and acurrent converter 85 b. Into the output computer 85 a, a target turningangle value, an actual turning angle value, and a motor rotation angleare input. The target turning angle value is output from the controller90 via the inboard LAN 91. The actual turning angle value is detected bythe turning angle sensor 62 equipped in the turning mechanism 30. Themotor rotation angle is detected by a rotation angle sensor 63 attachedto the turning motor 60. The rotation angle sensor 63 detects a rotationangle of a rotor of the turning motor 60. The output computer 85 agenerates an output torque value based on a deviation between the targetturning angle value and the actual turning angle value, and a motorrotation angle detected by the rotation angle sensor 63, and suppliesthe output torque value to the current converter 85 b. The currentconverter 85 b supplies a drive current corresponding to the outputtorque value to the turning motor 60. Thus, the turning motor 60 isdriven. The turning motor 60 is accordingly feedback-controlled so thatthe actual turning angle approaches the target turning angle value.

The propulsion motor controller 86 includes an output computer 86 a anda current converter 86 b. Into the output computer 86 a, a target torquevalue is input, and a motor rotation angle is input. The target torquevalue is output from the controller 90 via the inboard LAN 91. The motorrotation angle is detected by the rotation angle sensor 54 attached tothe propulsion motor 50. The rotation angle sensor 54 detects a rotationangle of a rotor portion 53 of the propulsion motor 50. Instead of arotation angle sensor 54, it is also possible that a rotation angle ofthe propulsion motor 50 is obtained by internal computing by the motorcontroller 45. The output computer 86 a generates an output torque valuebased on the target torque value and the motor rotation angle, andsupplies the output torque value to the current converter 86 b. Thecurrent converter 86 b supplies a drive current corresponding to theoutput torque value to the propulsion motor 50, and thus, the propulsionmotor 50 is driven. Accordingly, the propulsion motor 50 is controlledso that the target torque value is reached, and accordingly, apropulsive force satisfying the requested output is obtained.

The storing motor controller 87 includes an output computer 87 a and acurrent converter 87 b. Into the output computer 87 a, a target storingangle value and an actual storing angle value are input. The targetstoring angle value is output from the controller 90 via the inboard LAN91. The actual storing angle value is detected by a storing angle sensor82 equipped in the storing mechanism 8. The storing angle sensor 82detects an angle of a movable portion of the storing mechanism 8. Thestoring angle corresponds to an elevation angle (or depression angle) ofthe electric propulsion unit 4. For example, the storing angle may beabout 90 degrees, for example, at the actuating position, and may beabout 0 degrees, for example, at the storing position. Rotation of thestoring motor 80 may be transmitted to the movable portion (drivebracket 79) via a reducer 81. In this case, the storing angle sensor 82may detect a rotation angle of any of rotary shafts (including a motorshaft) disposed in a rotation transmission path from the storing motor80 to the movable portion. The output computer 87 a generates an outputtorque value based on a deviation between the target storing angle valueand the actual storing angle value, and supplies the output torque valueto the current converter 87 b. The current converter 87 b supplies adrive current corresponding to the output torque value to the storingmotor 80, and the storing motor 80 is accordingly driven. Thus, thestoring motor 80 is feedback-controlled so that the actual storing anglevalue approaches the target storing angle value, and accordingly, theelectric propulsion unit 4 is displaced between the storing position andthe actuating position.

The motor controller 45 transmits the output torque value, the actualturning angle value, and the storing angle value operated by the outputcomputers 85 a, 86 a, and 87 a to the controller 90 via the inboard LAN91.

The engine ECU 20 is equipped in the engine propulsion unit 3. Commandinformation such as a target throttle opening degree and a target shiftposition is output from the controller 90 via the inboard LAN 91 to theengine ECU 20. The engine ECU 20 controls a throttle opening degree ofthe engine 12 based on the target throttle opening degree, andaccordingly controls an output of the engine 12 (engine rotation speed).The engine ECU 20 controls the shift actuator 26 based on the targetshift position. Accordingly, the shift mechanism 18 is moved to a shiftposition (the forward position, the neutral position, or the backwardposition) corresponding to the target shift position. The engine ECU 20transmits an actual throttle opening degree, an actual shift position,and an actual engine rotation speed to the controller 90 via the inboardLAN 91.

Into the controller 90, shift lever position information (an output ofthe accelerator opening degree sensor 75 b) showing an operationposition of the shift lever 5 b is input. The shift lever 5 b is a shiftposition selecting operator to be operated by an operator to select ashift position. In the present preferred embodiment, the shift lever 5 bfunctions also as an accelerator (accelerator operating portion,accelerator lever) to be operated by an operator to set an acceleratoropening degree (accelerator operation amount). An operation amount ofthe shift lever 5 b is detected by the accelerator opening degree sensor75 b. Therefore, the controller 90 interprets output signals of theaccelerator opening degree sensor 75 b as shift lever positioninformation and accelerator opening degree information.

Operation angle information of the steering wheel 5 a (an output of theoperation angle sensor 75 a) is input to the controller 90.

Operation position information of the joystick 5 c (an output of thejoystick position sensor 75 c) is also input into the controller 90. Thejoystick 5 c is an example of an accelerator (accelerator operator,accelerator lever). An operation position of the joystick 5 c isdetected by the joystick position sensor 75 c. The controller 90interprets output signals of the joystick position sensor 75 c as asteering command signal and an accelerator command signal (acceleratoropening degree), etc.

Further, mode command information is input from the mode switch 5 d tothe controller 90. The mode switch 5 d is operated by an operator. Byoperating the mode switch 5 d, an operator is able to select an electricmode in which the electric propulsion unit 4 is used, an engine-onlymode in which the electric propulsion unit 4 is not used, and anautomatic mode in which switching between the electric mode and theengine-only mode is left to the controller 90.

The mode switch 5 d defines at least a portion of a propulsion modeswitching unit that switches between an engine propulsion allowing statein which generation of a propulsive force by the engine propulsion unit3 is allowed, and an electric propulsion allowing state in whichgeneration of a propulsive force by the electric propulsion unit 4 isallowed. The electric mode corresponds to the electric propulsionallowing state, and the engine-only mode corresponds to the enginepropulsion allowing state. In the automatic mode, due to an action bythe controller 90, the electric propulsion allowing state and the enginepropulsion allowing state are selected. In the electric mode, thecontroller 90 cancels the electric mode and puts the state into theengine propulsion allowing state as necessary. Thus, an action of thecontroller 90 also defines the propulsion mode switching unit. Theelectric propulsion allowing state and the engine propulsion allowingstate do not necessarily have to be selected alternatively. For example,when canceling the electric mode, the controller 90 may temporarilyallow both of the electric propulsion unit 4 and the engine propulsionunit 3 to generate propulsive forces. That is, when switching betweenthe electric propulsion allowing state and the engine propulsionallowing state, the state may be changed to a transition state in whichboth of the propulsion units 3 and 4 are allowed to generate propulsiveforces.

Various pieces of information are further input from the inboard LAN 91to the controller 90. More specifically, as information related to theelectric propulsion unit 4, an output torque value, an actual turningangle value, and an actual storing angle value, etc., are input. Asinformation related to the engine propulsion unit 3, an actual throttleopening degree, an engine rotation speed, etc., are input.

The controller 90 outputs, as described above, target turning anglevalues, target torque values, and target storing angle values inrelation to the electric propulsion unit 4. The controller 90 outputs atarget throttle opening degree and a target shift position related tothe engine propulsion unit 3.

In a preferred embodiment of the present invention, the controller 90 isconfigured or programmed to perform an interlock operation of thestoring mechanism 8 with generation of a propulsive force by the enginepropulsion unit 3. The controller 90 includes a CPU (Central ProcessingUnit) 93, and a memory 94 storing programs to be executed by the CPU 93.When the CPU 93 executes the programs, the controller 90 performsfunctions as a plurality of function processors. One of these functionsis an interlock controller that interlocks operation of the storingmechanism 8 and generation of a propulsive force by the enginepropulsion unit 3.

FIG. 7 is a flowchart showing a detailed example of interlockingoperation of the storing mechanism 8 and propulsive force generation bythe engine propulsion unit 3, and shows a processing example to berepeatedly performed by the controller 90.

The controller 90 judges whether the electric mode has been started(Step S1). When an electric mode starting condition is met, thecontroller 90 starts the electric mode. The electric mode startingcondition may be met by, for example, at least one of the followingConditions A1 and A2. Instead of Condition A2, the following ConditionA3 may be used.

Condition A1: The electric mode has been selected by the mode switch 5d.

Condition A2: The automatic mode is selected by the mode switch 5 d, theshift lever 5 b is at the neutral position, and the vessel speed hasdecreased to reach a predetermined value (for example, about 5 km/h) orless.

Condition A3: The automatic mode is selected by the mode switch 5 d, theshift lever 5 b is at the neutral position, the vessel speed is at apredetermined value (for example, about 5 km/h) or less, and thejoystick 5 c has been operated.

The electric mode is ended when a predetermined canceling condition ismet. The canceling condition may be met by, for example, at least one ofthe following Conditions B1, B2, B3, and B4.

Condition B1: The engine-only mode has been selected by the mode switch5 d.

Condition B2: The automatic mode is selected by the mode switch 5 d, andthe shift lever 5 b has been moved from the neutral position to anotherposition. That is, shifting-in (propulsive force generation) of theengine propulsion unit 3 has been commanded.

Condition B3: The automatic mode is selected by the mode switch 5 d, andthe shift lever 5 b has been moved by a predetermined angle (forexample, about 10 degrees) or more in an operation direction to increasethe output from a state in which the shift lever 5 b is in a range of apredetermined angle (for example, within about ±20 degrees) from theneutral position. That is, an operation intended to shift-in of theengine propulsion unit 3 (propulsive force generation) has beendetected.

Condition B4: The automatic mode is selected by the mode switch 5 d, andit has been detected that the shift lever 5 b is in a moving state for apredetermined period of time (for example, about 0.5 seconds) or more atan operation speed equal to or more than a predetermined speed (forexample, about 30 deg/sec). That is, an operation intended to generate alarge propulsive force has been detected.

When the state is out of the electric mode, the electric propulsion unit4 is at the storing position. When the electric mode is started (StepS1: YES), the controller 90 drives the storing motor 80 to move theelectric propulsion unit 4 to the actuating position (Step S2). For theconvenience of storing in the storing space 7 inside the propulsion unitattaching bracket 6, the electric propulsion unit 4 may be turned sothat its turning angle reaches an under-storage turning angle in thestored state. In this case, the controller 90 performs an operation tochange the turning angle of the electric propulsion unit 4 to a targetturning angle value, that is, a command value commanded by the steeringwheel 5 a or the joystick 5 c. More specifically, first, the controller90 stands-by until the storing angle reaches a predetermined turningstart allowing angle Ka or more, and when it reaches the turning startallowing angle (Step S3: YES), the controller allows turning (Step S4).Accordingly, the controller 90 actuates the turning motor 60 to startturning to the target turning angle value. The turning start allowingangle Ka is a storing angle set in advance to prevent the electricpropulsion unit 4 from interfering (colliding) with other elements ofthe vessel 1 when turning.

When the actual turning angle value enters a predetermined angle range(for example, a target turning angle value ±Δθ, Δθ is a constant) aroundthe target turning angle value (Step S5: YES), and the storing anglereaches a predetermined actuation starting angle Kb (Kb>Ka) (Step S6:YES), the controller 90 allows driving of the propulsion motor (StepS7). The actuation starting angle Kb is a storing angle in a state inwhich the electric propulsion unit 4 has sufficiently approached theactuating position without posing a problem even when it generates apropulsive force.

After allowing driving of the propulsion motor 50, the controller 90outputs a target torque value for the propulsion motor 50 according toan accelerator opening degree (Step S8). According to this target torquevalue, the propulsion motor 50 is driven. Specifically, the acceleratoropening degree is a value corresponding to a position of the shift lever5 b or a position of the joystick 5 c, and is an accelerator commandcorresponding to an operator's input.

The controller 90 further judges whether the accelerator opening degreeis equal to or more than a predetermined engine propulsion threshold Ta.When the accelerator opening degree is less than the engine propulsionthreshold Ta (Step S9: NO), the process returns to Step S8, a targettorque value corresponding to the accelerator opening degree is set andthe propulsion motor 50 is driven, and a corresponding propulsive forceis generated from the electric propulsion unit 4.

When the accelerator opening degree is equal to or more than the enginepropulsion threshold Ta (Step S9: YES), and a large propulsive force isaccordingly requested, a process to generate a propulsive force by theengine propulsion unit 3 is performed. That is, the controller 90 stopsthe output of the electric propulsion unit 4 (Step S10), and turns theelectric propulsion unit 4 to the under-storage turning angle (stepS11). Further, in order to move the electric propulsion unit 4 to thestoring position, the controller 90 issues a command to drive thestoring motor 80 (Step S12). Then, the controller 90 checks whetherstoring of the electric propulsion unit 4 has been completed (Step S13).For example, by judging whether the storing angle is equal to or lessthan a predetermined storage determining angle Kc, the controller 90 maycheck whether the electric propulsion unit 4 has reached a positionsufficiently close to the storing position. Alternatively, thecontroller may detect completion of storing of the electric propulsionunit 4 by a detection switch 83 (refer to FIG. 5, for example, a microswitch) actuated by the movable portion of the storing mechanism 8 in astoring state.

When storing of the electric propulsion unit 4 is completed (Step S13:YES), the controller 90 cancels the electric mode (Step S14), and allowsgeneration of a propulsive force by the engine propulsion unit 3 (StepS15). Then, the controller 90 provides command values of a targetthrottle opening degree, a target shift position, and a target turningangle, etc., to the engine ECU 20 (Step S16). By setting the targetshift position to the forward position or the backward position, in theengine propulsion unit 3, a driving force of the engine 12 istransmitted to the propeller 13, and a propulsive force is generatedfrom the engine propulsion unit 3. At this time, the electric propulsionunit 4 is located at the storing position, so that little or notraveling resistance is generated.

Thus, according to a preferred embodiment of the present invention, evenwithout a special operation by a user to store the electric propulsionunit 4, generation of a propulsive force by the engine propulsion unit 3and storing of the electric propulsion unit 4 are interlocked with eachother. Accordingly, when the vessel 1 travels by a propulsive force ofthe engine propulsion unit 3, traveling resistance caused by theelectric propulsion unit 4 is significantly reduced or prevented.Accordingly, fuel efficiency is improved and excellent travelingperformance is obtained.

In addition, in a preferred embodiment of the present invention, whenthe accelerator opening degree reaches the engine propulsion thresholdTa or more, the storing motor 80 is driven, the electric propulsion unit4 is stored, and generation of a propulsive force by the enginepropulsion unit 3 is allowed. Therefore, a large propulsive force isgenerated by the engine propulsion unit 3 to make the vessel 1 travel,and at this time, traveling resistance caused by the electric propulsionunit 4 is significantly reduced or prevented.

In a preferred embodiment of the present invention, by operating themode switch 5 d, a user is able to select whether he/she uses theelectric mode. Accordingly, a user is able to select use of the electricpropulsion unit 4 at his/her own will.

In a preferred embodiment of the present invention, even when generationof a propulsive force by the engine propulsion unit 3 is not allowed,operation of the engine 12 is allowed. Therefore, when the enginepropulsion unit 3 is provided with a power generator, by operating theengine 12, a battery (not shown) equipped in the hull 2 is charged andelectric facilities (not shown) equipped in the vessel 1 are able to beused.

FIG. 8 is a diagram to describe a second preferred embodiment of thepresent invention, and is a flowchart showing an example of a process tobe repeatedly performed by the controller 90 in association withinterlocking operation of the storing mechanism 8 and propulsive forcegeneration by the engine propulsion unit 3. In the description of thepresent preferred embodiment, FIG. 1 to FIG. 6 described above arereferred to again. In FIG. 8, steps in which substantially the sameprocess as in each step shown in FIG. 7 described above is performed aredesignated by the same reference signs.

In the present preferred embodiment, when the accelerator opening degreereaches the engine propulsion threshold Ta or more in the electric mode(Steps S8 and S9), prior to stopping the output of the electricpropulsion unit 4 (Step S10) and storing of the electric propulsion unit4 (Steps S11 to S13), and cancellation of the electric mode (Step S14),output (generation of a propulsive force) of the engine propulsion unit3, are allowed (Step S15). Then, the controller 90 provides variouscommands to the engine ECU 20 of the engine propulsion unit 3 (StepS16). In this state, the controller 90 judges whether the enginepropulsion unit 3 has generated a propulsive force (Step S20). Forexample, when the shift position is at the forward position or thebackward position, and the engine rotation speed or the throttle openingdegree is equal to or more than a predetermined threshold, thecontroller 90 may judge that the engine propulsion unit 3 has generateda propulsive force. When the engine propulsive device 3 generates nopropulsive force (Step S20: NO), the process returns to Step S8, andgeneration of a propulsive force by the electric propulsion unit 4 iscontinuously allowed. On the other hand, when the engine propulsion unit3 generates a propulsive force (Step S20: YES), the controller 90 stopsthe propulsion motor 50 of the electric propulsion unit 4 (Step S10),and further drives the storing motor 80, etc., to store the electricpropulsion unit 4 (Steps S11 to S13). Then, the controller 90 cancelsthe electric mode (Step S14) and ends the process.

Thus, in the present preferred embodiment, when the engine propulsionunit 3 actually generates a propulsive force, in response to this, theelectric propulsion unit 4 is stored. Therefore, in a state in which theengine propulsion unit 3 generates a propulsive force, an operation tostore the electric propulsion unit 4 is performed. The engine propulsionunit 3 and the electric propulsion unit 4 may be temporarily put into atransition state in which both of these generate propulsive forces.

FIGS. 9A and 9B are diagrams to describe a third preferred embodiment ofthe present invention, and are flowcharts showing examples of processesof the controller 90 in association with interlocking operation of thestoring mechanism 8 and propulsive force generation by the enginepropulsion unit 3. The controller 90 repeatedly performs in parallel acontrol process for the electric propulsion unit 4 shown in FIG. 9A anda control process for the engine propulsion unit 3 shown in FIG. 9B. InFIGS. 9A and 9B, steps in which substantially the same process as ineach step shown in FIG. 7 described above is performed are designated bythe same reference signs.

In the first preferred embodiment shown in FIG. 7 described above, afterthe electric propulsion unit 4 is stored, output (generation of apropulsive force) by the engine propulsion unit 3 is allowed. In thesecond preferred embodiment shown in FIG. 8, when output (generation ofa propulsive force) of the engine propulsion unit 3 starts, the electricpropulsion unit 4 is stored. On the other hand, in the third preferredembodiment, when the accelerator opening degree reaches a storingthreshold Tb or more (Step S32: YES), the electric propulsion unit 4 isstored (Steps S11 to S13). On the other hand, when the acceleratoropening degree reaches the engine propulsion threshold Ta or more (StepS9: YES), output of the engine propulsion unit 3 is allowed (Step S15).More specifically, as shown in FIG. 9A, when the accelerator openingdegree reaches the storing threshold Tb or more (Step S32), thecontroller 90 stops output of the electric propulsion unit 4 (Step S10),stores the electric propulsion unit 4 (Steps S11 to S13), and cancelsthe electric mode (Step S14). In parallel with this operation, in theelectric mode (Step S31: YES), when the accelerator opening degreereaches the engine propulsion threshold Ta or more (Step S9: YES), thecontroller 90 allows output (generation of a propulsive force) by theengine propulsion unit 3 (Step S15). Then, the controller 90 generates acommand value for the engine propulsion unit 3 (Step S16). When thestate is not the electric mode (Step S31: NO), the controller 90 allowsoutput of the engine propulsion unit 3 (Step S15), and generates acommand value for the engine propulsion unit 3 (Step S16). Therefore, apropulsive force is generated by the engine propulsion unit 3. In theelectric mode (Step S31: YES), when the accelerator opening degree isless than the engine propulsion threshold Ta (Step S32: NO), the processis ended without allowing output of the engine propulsion unit 3.

Thus, in the present preferred embodiment, storing of the electricpropulsion unit 4 and allowing output of the engine propulsion unit 3are performed according to the accelerator opening degree, so thatstoring of the electric propulsion unit 4 and propulsive forcegeneration by the engine propulsion unit 3 are interlocked with eachother.

The storing threshold Tb may be equal to or different from the enginepropulsion threshold Ta. The storing threshold Tb may be larger than theengine propulsion threshold Ta, or may be smaller than the enginepropulsion threshold Ta.

Various preferred embodiments of the present invention have beendescribed above, and the present invention can be further carried out byother preferred embodiments.

For example, in the preferred embodiments described above, the enginepropulsion unit 3 is an outboard motor; however, it may be another typeof propulsion unit such as an inboard motor, an inboard-outdrive engine(stern drive), etc.

In the preferred embodiments described above, the storing mechanism 8preferably stores the electric propulsion unit 4 in the storing space 7by displacing the electric propulsion unit 4, and accordingly reducestraveling resistance caused by the electric propulsion unit 4. However,storing of the electric propulsion unit 4 does not necessarily have toinvolve displacement of the electric propulsion unit 4. For example, astoring mechanism structured to reduce traveling resistance caused bythe electric propulsion unit 4 by disposing a streamline-shaped cover atthe front side of the electric propulsion unit 4, may be used. In thiscase, the cover is preferably displaced between a storing position atwhich the cover is disposed at the front side of the electric propulsionunit 4 to put the electric propulsion unit 4 into a stored state, and anactuating position at which the cover is retracted from the front sideof the electric propulsion unit 4 to put the electric propulsion unit 4into an actuated state.

Further, in the preferred embodiments described above, by operating themode switch 5 d, the electric mode and the engine-only mode are able tobe manually selected, and the automatic mode is able be selected.However, it is also possible that the mode switch 5 d is not providedand only the automatic mode is provided. To the contrary, it is alsopossible that the automatic mode is not provided, and the electric modeand the engine-only mode are selected by the mode switch 5 d.

When traveling in shallow water using the electric propulsion unit 4,the tilt trim actuator 27 of the engine propulsion unit 3 may beactuated to put the engine propulsion unit 3 into a tilted-up state.

The storing mechanism 8 is preferably arranged so that in a case ofcollision with an obstacle in the water, the electric propulsion unit 4is flipped up to the storing position by an impact of the collision.Accordingly, breakage of the electric propulsion unit 4 is avoided.

While preferred embodiments of the present invention have been describedabove, it is to be understood that variations and modifications will beapparent to those skilled in the art without departing from the scopeand spirit of the present invention. The scope of the present invention,therefore, is to be determined solely by the following claims.

What is claimed is:
 1. A propulsion system for a vessel comprising: anengine propulsion unit that provides a propulsive force to a hull byusing an engine as a power source; an electric propulsion unit thatprovides a propulsive force to the hull by using an electric motor as apower source; a motor that performs a storing operation to move theelectric propulsion unit from an actuating position to a storingposition to store the electric propulsion unit; and a controllerprogrammed to cause the motor to perform the storing operation inaccordance with generation of the propulsive force by the enginepropulsion unit.
 2. The vessel propulsion system according to claim 1,wherein, in response to actuation of the motor to store the electricpropulsion unit, the controller is programmed to allow generation of thepropulsive force by the engine propulsion unit.
 3. The vessel propulsionsystem according to claim 2, wherein, when an accelerator operationamount, which is an operation amount of an accelerator that is operatedby a vessel operator to adjust a propulsive force of the vessel, reachesa predetermined threshold or more, the controller is programmed to causethe motor to perform the storing operation.
 4. The vessel propulsionsystem according to claim 1, wherein, in response to generation of apropulsive force by the engine propulsion unit, the controller isprogrammed to cause the motor to perform the storing operation.
 5. Thevessel propulsion system according to claim 4, wherein, when anaccelerator operation amount, which is an operation amount of anaccelerator that is operated by a vessel operator to adjust a propulsiveforce of the vessel, reaches a predetermined threshold or more, thecontroller is programmed to allow generation of the propulsive force bythe engine propulsion unit.
 6. The vessel propulsion system according toclaim 1, wherein the controller is programmed to cause the motor toperform the storing operation when an accelerator operation amount,which is an operation amount of an accelerator that is operated by avessel operator to adjust a propulsive force of the vessel, reaches apredetermined storing threshold or more, and to allow generation of thepropulsive force by the engine propulsion unit when the acceleratoroperation amount reaches an engine propulsion threshold or more.
 7. Avessel comprising: a hull; and a vessel propulsion system on the hull,the vessel propulsion system including: an engine propulsion unit thatprovides a propulsive force to the hull by using an engine as a powersource; an electric propulsion unit that provides a propulsive force tothe hull by using an electric motor as a power source; a motor thatperforms a storing operation to move the electric propulsion unit froman actuating position to a storing position to store the electricpropulsion unit; and a controller programmed to cause the motor toperform the storing operation in accordance with generation of thepropulsive force by the engine propulsion unit.
 8. The vessel accordingto claim 7, wherein, in response to actuation of the motor to store theelectric propulsion unit, the controller is programmed to allowgeneration of the propulsive force by the engine propulsion unit.
 9. Thevessel according to claim 8, wherein, when an accelerator operationamount, which is an operation amount of an accelerator that is operatedby a vessel operator to adjust a propulsive force of the vessel, reachesa predetermined threshold or more, the controller is programmed to causethe motor to perform the storing operation.
 10. The vessel according toclaim 7, wherein, in response to generation of the propulsive force bythe engine propulsion unit, the controller is programmed to cause themotor to perform the storing operation.
 11. The vessel according toclaim 10, wherein, when an accelerator operation amount, which is anoperation amount of an accelerator that is operated by a vessel operatorto adjust a propulsive force of the vessel, reaches a predeterminedthreshold or more, the controller is programmed to allow generation ofthe propulsive force by the engine propulsion unit.
 12. The vesselaccording to claim 7, wherein the controller is programmed to cause themotor to perform the storing operation when an accelerator operationamount, which is an operation amount of an accelerator that is operatedby a vessel operator to adjust a propulsive force of the vessel, reachesa predetermined storing threshold or more, and to allow generation ofthe propulsive force by the engine propulsion unit when the acceleratoroperation amount reaches an engine propulsion threshold or more.